This relates generally to computer processing using virtualization.
Computer systems are subject to attack by malware. Unauthorized software may infect a computer system and cause the computer to operate in improper ways. Generally software running on a central processing unit is controlled by various techniques such as rings and range registers. However, other co-processors on the same system may operate independently of these protections and thus may provide an avenue for system attack.
One known solution is to use virtualization technology including the VT-d virtualization technology available from Intel Corporation. The VMX-root mode operation is primarily intended for use by a virtual machine monitor (VMM) and its operation is like that without virtualization. The VMX-nonroot mode is controlled by a virtual machine monitor (VMM) and is designed to support virtualization.
Sometimes co-processors need regulated access to system memory at the granularity of the software executing on the co-processor. The software modules that execute on the graphics processor are called shader kernels and the system memory access is needed at the granularity of the shader kernel.